Maps.md

Maps

Note: This is WIP. Some data structures are incomplete, others may be incorrect.

Maps are stored in MAP_DATA.AMB. Each resource describes one in-game map, with 2D maps and Labyrinths sharing much of the file structure. The files consist of the following sections:

• Header
• Event descriptions (e.g., popup messages, chests, locked doors, or transitions to other maps)
• NPC references (not including the actual NPC descriptions, which are in CHARDATA.AMB)
• A magic 9 byte sequence
• 3D maps / Labyrinths only: LabInfo blocks (meaning currently unclear)
• The actual map
• 2D maps only: An overlay tile map, drawn over the preceding map
• A hotspot map, which maps map locations to event descriptions
• NPC locations and/or movement routes

Map Header and Structure

Offset	Format	Name	Description
0	u8	magic number	= 0xff
1	u8	fill byte	= 0x00
2	u16	tileset / background	2D maps: tileset (1 or 2). Labyrinths: LabData resource describing the graphics, + 1
4	u8	labyrinth marker	00 for top-down 2D maps, 01 for Labyrinths (dungeons, towns)
5	u8	flags	See below
6	u8	song	If ≠ 00, set active song to this one
7	u8	width	in # tiles
8	u8	height	in # tiles
9	char[30]	name	map name, padded with 0x20, and 0x00-terminated
38	event[254]	events	10 bytes per event
a14	npc[24]	NPCs	NPC list, See below
abc	u16	max steps per day	= 0x120 (288), total amount of 5-minute steps per day
abe	u8	months per year	= 12
abf	u8	days per month	= 30
ac0	u8	hours per day	= 24
ac1	u8	minutes per hour	= 60
ac2	u8	minutes per step	= 5
ac3	u8	hours per daytime	= 12
ac4	u8	hours per nighttime	= 12
ac5...			varies between 2D maps and Labyrinths, see below
	LabInfo[..]	labinfo	Labyrinth only: Labyrinth tile descriptions
	u8[width * height]	map[0]	map data
	u8[width * height]	map[1]	2D only: overlay map
	u8[width * height]	hotspots	hotspot map. If hotspot[pos] = n > 0, then event[n - 1] triggers at pos
	u8[..]	NPC coordinates	See below

Map Flags

The map flags indicate light sources, whether resting is possible etc.:

Flag	Name	Exclusivity	Meaning	Example maps
0x01		A	Light: always	Sir Marillon's Tomb, Family home
0x02		A	Light: sunlight only	Overworld, Twinlake Graveyard, Twinlake city
0x04		A	Light: none	Lord Drebin's Cellar, Twinlake Sewers
0x08			"Mapshow" spell allowed	Most maps. NOT some advanced dungeons, such as Castle of Manyeye (minus the Tower)
0x10			Can rest here	Overworld, Twinlake sewers, Family home. NOT Twinlake city or graveyard.
0x20		B	Wilderness	All overworld maps
0x40		B	City	Twinlake Graveyard, Twinlake City
0x80		B	Dungeon	Sir Marillon's Tomb, Twinlake Sewers

• A: Precisely one of {01, 02, 04} is set on every map
• B: Precisely one of {20, 40, 80} is set on every map

Light

The light is calculated as follows:

• If active character is blind, all dark.
• Otherwise if Light bit is 1 (flags & 0x01 != 0), just show full brightness.
• Otherwise if Light bit is 0 (flags & 0x01 == 0), check for LightChange bit (flags & 0x02).
• If set, get the light radius by the hour.
  • Use this table: 16,16,16,16,16,16,40,64,200,200,200,200,200,200,200,200,200,64,64,40,16,16,16,16,16.
  • Any active light spell will add its effect (multiplied by 8) to the radius.
• If the change bit was 0 instead, check the dark bit (flags & 0x04).
• If this is not set, just do nothing (no change). I guess no map uses this (all 3 bits would be 0).
• Otherwise check travel type first. Superchicken mode (cheat) grants full light.
• Otherwise if no light spell is active, use full darkness.
• Otherwise use a radius of 16 + (the light spell effect multiplied by 8).

2D Maps

Offset	Format	Name	Description
...			(cf. Map Header and Structure)
ac5	u8[width * height]	map[0]	map data
ac5 + mapsize	u8[width * height]	map[1]	overlay map
ac5 + mapsize * 2	u8[width * height]	hotspots	hotspot map
ac5 + mapsize * 3	u8[..]	NPC coordinates	See below

where:

• mapsize = height * width

Labyrinths

Offset	Format	Name	Description
...			(cf. Map Header and Structure)
ac5	u8	#labinfo	Number of LabInfo blocks
ac6	u8[4 * #labinfo]	labinfo[i].flags	See below
ac6 + #labinfo * 4	u8[#labinfo]	labinfo[i].primary	See below
ac6 + #labinfo * 5	u8[#labinfo]	labinfo[i].secondary	See below
ac6 + #labinfo * 6	u8[#labinfo]	labinfo[i].color	See below
ac6 + labinfosize	u8[width * height]	map[0]	map data
ac6 + labinfosize + mapsize	u8[width * height]	hotspots	hotspot map
ac6 + labinfosize + mapsize * 2	u8[..]	NPC coordinates	See below

where:

• labinfosize = #labinfo * 7
• mapsize = height * width

LabInfo blocks

LabInfo blocks consist of 7 bytes each and describe the meaning of the tile numbers on the map. They reference the Labyrinth's associated LabData resource.

• One chunk of u32 flags (labinfo.flags, below)
• Three chunks of u8 blocks (labinfo.primary, labinfo.secondary, and labinfo.color, respectively, below)

Labinfo	Meaning	Notes
flags	flags	Tile Flags
primary	primary lab block	Index into the labblock_ref table for LabData. If overlay, secondary gives the underlay.
secondary	secondary lab block	Only used if primary was an overlay. Index into the labblock_ref table for LabData.
color	Minimap color index	Color on thr minimap, observed values: [00-0c, 0e-0f]

NPCs

NPC map descriptions are split into two parts, which I will here call the NPC list and the NPC movement routes.

• NPC list: always starts at a14
• NPC movement routes: always start after the hotspot map (making them the final part of each map resource)

NPC list

There are always precisely 24 (0x18) NPCs declared. NPC declarations are chunked into six parts, with 24 entries each:

Offset	type	Name	Meaning
a14	u16[24]	npc[i].personality	0 if disabled, otherwise NPC ID or popup message plus 1
a44 (= a14 + 24 * 2)	u8[24]	npc[i].sprite	NPC sprite (on the active tile map)
a5c (= a14 + 24 * 3)	u8[24]	npc[i].move	Travel mode of the NPC (basically collision classes)
a74 (= a14 + 24 * 4)	u8[24]	npc[i].flags	See below
a8c (= a14 + 24 * 5)	u8[24]	npc[i].day	Spawn day (see flags, must match current day of month)
aa4 (= a14 + 24 * 6)	u8[24]	npc[i].month	Spawn month (see flags, must match current month)

Flags	Name	Exclusivity	Meaning
flags & 0x01	type	-	0: person, 1: monster
flags & 0x02	random/path	Persons only	0: path, 1: walk around randomly
flags & 0x04	hunt/stay	Monsters only	0: stay, 1: hunt player
flags & 0x08	spawn date	Persons only	0: always there, 1: only on specific date
flags & 0x10	popup-only	Persons only	talking to NPC pops up message

Talking to NPCs

When the player talks to an NPC, the following happens:

• If popup-only is set, then pop up the MAPTEXT message indexed by personality - 1.
• If attack is set, enter combat for the combat layout (MON_DATA) indexed by personality - 1.
• Otherwise, enter chat mode for NPC from CHARDATA, indexed by personality - 1.

NPC Positions and Movement Routes

For each NPC with a nonzero personality, the map stores some number of bytes for their position and/or movement route. There seem to be three possible movment modes for NPCs, which determine how many coordinates the movment routes table store:

Movement mode	Indication	# coordinates
ATTACK	attack is set	1
RANDOM-WALK	random-walk is set	1
CIRCUIT	neither attack nor stationary is set	0x120 = 288

The movement routes are stored in the same order in which the NPCs are stored:

• first all x coordinates for the NPC
• then all y coordinates for the NPC

Note:

• All coordinates are +1 relative to map positions.
• Coordinate values of 6 mean tha tthe NPC disappears.
• NPCs that enter a chair or a bed are drawn suitably. The party cannot chat with NPCs that are in bed.
• The coordinates might plausibly be broken up across the day cycle.

For instance, if we have two stationary NPCs, then one circuit NPC, and another stationary NPC, the game will store

• NPC[0].x (1 byte)
• NPC[0].y
• NPC[1].x
• NPC[1].y
• NPC[2].x[0..0x120] (0x120 bytes)
• NPC[2].y[0..0x120]
• NPC[3].x
• NPC[3].y

Movement algorithm:

• RANDOM-WALK: Every four party movements (?), move into one direction at random.
• ATTACK: move one field (incl. diagonally) closer to the player. Unknown: do the NPCs see the player through walls?
• CIRCUIT: Iterate over the coordinates in the coordinate table. Coordinates may repeat, indicating that the NPC stays still for a few rounds before moving on.

Unknown: can NPCs trigger events?

Tile Map and Overlay Map

The overlay map (only present in 2D maps) is functionally identical to the tile map, so we refer to them as map[0] and map[1], respectively, and refer to both jointly as "tile maps".

Tile maps store tiles in row-major order. Tile 0 indicates "no tile" (nothing to draw), while tile 1 is the first tile (index 0).

Hotspot Map

The hotspot map stores u8 values in row-major order:

• 0 means "no hotspot"
• n > 0 means "trigger event n-1". Conditions for triggering an event vary by event.